System and method for washing items

ABSTRACT

A system ( 10 ) for washing items ( 12 ) with water, comprising a water inlet ( 18 ) and a container ( 13 ) for receiving the items ( 12 ) to be washed. The system ( 10 ) comprises a water purification apparatus ( 19 ) for purifying water introduced through said water inlet ( 18 ) to produce purified water. The water purification apparatus ( 19 ) comprises at least one filter ( 25, 29, 30 ) for filtering off particulate solids, a reverse osmosis device ( 26 ), and at least one deionizing filter ( 27, 31 ). The system ( 10 ) further comprises a reservoir ( 20 ) for storing purified water produced by the water purification apparatus ( 19 ), said reservoir ( 20 ) being connected to said water purification apparatus ( 19 ) and said container ( 13 ), so that the items ( 12 ) are washable inside the container ( 11 ) with the purified water. Disclosed is also a method for washing items.

FIELD OF THE INVENTION

The invention relates to a system and a method for washing items. Morespecifically, the present invention relates to a system and a method forwashing items with processed water or purified water, wherein the amountof, e.g. salts has been reduced. This type of systems is generally usedfor washing clothes and similar, wherein the system comprises a washingmachine (also called laundry machine or clothes washer). Such washingmachines are used as household appliances for domestic use as well asfor larger scale laundry, such as in laundry facilities of apartmentblocks, hospitals, etc., and for commercial and industrial laundry. Thistype of systems can also be used for washing other types of items, suchas dishes and other eating utensils, wherein the system comprises adishwasher. This type of systems can also be used for washing othertypes of items.

PRIOR ART

There are devices and systems for washing items with water in the priorart. One such type of device is for example disclosed inUS2214100131863. US2214100131863 discloses a device in the form of awater-conducting household appliance, such as a washing machine, forwashing items by means of water. The device comprises a container foritems to be washed and desalination apparatus being constructed as anion exchanger for reducing the amount of salt in the water. A reservoiris connected to the desalination apparatus for storing water with ahigher salt concentration.

A problem with such devices and systems for washing items according toprior art is that the use thereof for washing items, such as laundry inthe form of clothes, etc., has a considerable negative influence on theenvironment.

Another problem of such prior art devices and systems is that the costfor using the device for washing can be quite expensive.

SUMMARY OF THE INVENTION

An object of the present invention is to avoid the problems of the priorart devices and systems for washing items. The system and methodaccording to the invention result in cost efficient and environmentallyfriendly washing of items within industry as well as for domestic use,particularly including washing of clothes and other laundry infacilities having a laundry room serving a plurality of households orincluding a plurality of washing machines.

The present invention relates to a system for washing items with water,comprising a water inlet and a container for receiving the items to bewashed, characterised in that the system comprises a water purificationapparatus for purifying water introduced through said water inlet toproduce purified water, the water purification apparatus comprising atleast one filter for filtering off particulate solids, a reverse osmosisdevice, and at least one deionizing filter, and, wherein the systemfurther comprises a reservoir for storing purified water produced by thewater purification apparatus, said reservoir being connected to saidwater purification apparatus and said container, so that the items arewashable with the purified water. It has surprisingly been found thatitems, such as laundry, can be washed and cleaned satisfactorily bymeans of the purified water without use of, or at least with reducedamounts of, detergents or tensides. This result in cost savings and lessnegative influence on the environment due to reduced use of detergentsfor washing. Hence, the items can be washed with the purified wateralone without use of detergents or tensides.

The system can be arranged for connection to a common water supplynetwork, such as a municipal water supply network, domestic water supplynetwork or similar. Hence, ordinary and commonly used tap water can beused by the system, wherein said tap water is purified to form thepurified water and then used for washing.

The water pressure from the water supply network can be used to conductthe water to and through the water purification apparatus and, also tothe reservoir. Hence, the water purification apparatus can functionwithout a circulation pump. Alternatively, the system can comprise oneor more pumps for pumping water to and/or through the system and thewater purification apparatus thereof, such as from the reservoir to awashing machine or dishwasher. Optionally, the system can comprise oneor more pumps for providing a suitable working pressure for the reverseosmosis device and, if desired, the one or more deionizing filters. Theone or more pumps can be arranged for providing a working pressure ofabout 700 kPa of the reverse osmosis device and the one or moredeionizing filters. Hence, due to the one or more pumps the reverseosmosis device and the deionizing filters can function effectively for along time.

The reverse osmosis device can be arranged between the filter and thedeionizing filters, wherein the water is purified to a specified extentwhen conducted to the deionizing filters. This results in an effectivepurification and a long life time of the deionizing filters.

The filter can be a filter pack comprising a sediment filter, a carbonfilter and a softener filter. The filters can be arranged in saidconsecutive order and can be followed by the reverse osmosis device, afirst deionizing filter and a second deionizing filter. This set up ofwater purification steps results in a highly purified water andeffective use of the components of the water purification apparatus.

The system can comprise a heater for heating incoming water to, e.g. 25°C. before entering into the water purification, i.e. before entering theone or more filters or at least before entering the reverse osmosisdevice. This will result in efficient purification and a long life timeof the reverse osmosis device. It can also result in a reliablemeasuring of conductivity of purified water for estimation of the puritythereof.

The water purification apparatus can be arranged for providing purifiedwater with low or substantially no conductivity. For example, the waterpurification apparatus is arranged for providing purified water havingsubstantially no charge. The water purification apparatus can bearranged for providing purified water with 0-5 or 0-2 ppm totaldissolved solids, e.g. measured with a TDS meter, e.g. at a specifiedtemperature such as 25° C. This will provide highly purified water,which efficiently washes items for cleaning thereof.

Such highly purified water has surprisingly been found to clean theitems, such as laundry, in the system to such an extent that no tensidesor detergents seem to be required for obtaining the desired cleaningresult.

The present invention also relates to a method for washing items withwater, comprising the steps of

a) conducting water from a water supply to a water inlet of a system forwashing said items,

b) conducting said water to a water purification apparatus for purifyingsaid water,

c) filtering off particulate solids from the water inside the waterpurification apparatus,

d) purifying the water by means of reverse osmosis inside the waterpurification apparatus,

e) filtering the water through at least one deionizing filter inside thewater purification apparatus,

f) conducting the purified water to a reservoir for storing the purifiedwater,

g) conducting the purified water from the reservoir to a container withthe items to be washed, and

h) washing the items inside the container with the purified water fromthe water purification apparatus.

The method according to the invention makes it possible to obtainpurified water from tap water or similar for washing the itemsefficiently, wherein the items can be cleaned without the use oftensides or detergents.

Further characteristics and advantages of the present invention willbecome apparent from the description of the embodiments below, theappended drawings and the dependent claims.

SHORT DESCRIPTION OF THE DRAWINGS

The invention will now be described more in detail with the aid ofembodiments and with reference to the appended drawings, in which

FIG. 1 is a schematic front view of a system for washing items accordingto one embodiment of the invention, wherein the system comprises awashing machine,

FIG. 2 is a schematic front view of a system for washing items accordingto one embodiment of the invention, wherein the system comprises adishwasher,

FIG. 3 is a schematic view illustrating a water purifying apparatus ofthe system according to one embodiment,

FIG. 4 is a schematic view illustrating a water purifying apparatus ofthe system according to another embodiment,

FIG. 5 is a schematic diagram showing a water purification apparatusaccording to FIG. 4 connected to a plurality of washing machines, and

FIG. 6 is a schematic diagram showing a water purification apparatusaccording to FIG. 4 connected to a washing machine and a dishwasher.

THE INVENTION

Referring to FIG. 1 a system 10 for washing items according to oneembodiment is disclosed. The system 10 according to FIG. 1 comprises awashing machine 11 for washing items 12, such as clothes, linen andsimilar. For example, the system 10 is a household appliance for washinglaundry. According to one embodiment the system 10 is arranged forserving a plurality of households for washing laundry. For example, thesystem 10 includes one or more washing machines 11 of a laundry room inan apartment block or similar. For example, the system 10 is arrangedfor washing items 12, such as laundry, without using tensides ordetergents. Hence, according to one embodiment the system 10 is arrangedfor simultaneously washing a plurality of items 12.

The system 10, or the washing machine 11 of the system 10, comprises acontainer 13 for accommodating the items 12 to be washed. The system 10comprises a door 14 for closing the container 13 and for loading ofitems 12 into the container 13. For example, the container 13 is arotating laundry drum of conventional type, wherein the items 12 to bewashed are loaded into the container 13 and rotated therein. The system10 also comprises a control panel 15 for setting or controlling awashing program to be used. The control panel 15 is, for example, ofconventional type and includes buttons 16 and a display 17 or similarmeans for controlling the system 10 or the washing machine 11 thereof.

The system 10 further comprises a water inlet 18, a water purificationapparatus 19, a reservoir 20 and a tubing 21. A part of the water inlet18, the water purification apparatus 19, the reservoir 20 and the tubing21 are illustrated by means of dashed lines in FIG. 1. The water inlet18 is arranged to be connected to a municipal water supply network orsimilar for allowing water, such as conventional tap water, from saidwater supply network to enter the system 10. The water inlet 18 isconnected to the water purification apparatus 19 for conducting waterfrom the water supply network to the water purification apparatus 19.The water purification apparatus 19 is arranged for purifying water fromthe water inlet 18 and produce purified water, which is described morein detail below. The water purification apparatus 19 is connected to thereservoir 20, which reservoir 20 is arranged for storing purified water,i.e. the water purified by the water purifying apparatus 19. Thereservoir 20 is connected to the container 13 through the tubing 21,wherein purified water stored in the reservoir 20 can be conducted tothe container 13 on demand for washing items 12 therein. In theembodiment of FIG. 1 the system 10 comprises an optional pump 22 forpumping water from the water inlet 18 to the water purificationapparatus 19 and further to the reservoir 20. Alternatively, the waterpressure from the water supply network is used for conducting water toand through the water purification apparatus. In the illustratedembodiment the system 10 also comprises a pumping device 23 for pumpingpurified water from the reservoir 20 to the container 13 for washingitems therein. For example, the washing machine 11 comprises the pumpingdevice 23. The pump 22 and the pumping device 23 are illustrated bymeans of dashed lines in FIG. 1.

With reference to FIG. 2 an alternative embodiment is illustrated,wherein the system 10 comprises a dishwasher 24 for domestic orindustrial use. For example, the system 10 comprises a dishwasher 24 forhandling dishes, eating utensils, pots, pans and similar in arestaurant, school or similar type of dining hall. For example, thesystem 10 is arranged for washing items, such as dishes, without usingtensides or detergents.

According to the embodiment of FIG. 2 the system 10, or the dishwasher24, comprises the container 13. For example, the container 13 forms aconventional dishwasher cleaning compartment. The dishwasher 24 furthercomprises the door 14 for closing the container 13, and the controlpanel 15, for example with buttons 16 and a display 17, for controllinga washing program. The system 10 also comprises the water inlet 18, thewater purification apparatus 19, the reservoir 20 and the tubing 21. Inthe embodiment of FIG. 2 the system 10 also comprises the pumping device23 for pumping purified water from the reservoir 20 to the container 13during washing of the items in the container 13.

The water purification device 19 according to one embodiment isdisclosed more in detail in FIG. 3. The water purification apparatus 19is arranged for purifying water from a water supply network, such as amunicipal water supply network, providing tap water or similar todifferent types of facilities, such as domestic houses, apartmentbuildings, commercial buildings and industry.

Conductivity is one measure to determine the degree of purity of water.Conductance meters can be used for such determinations. Conductivity isgiven as μS/cm (microSiemens per centimeter). Tap water can probablyhave a conductivity of 700-900 μS/cm. Values for distilled water hasbeen indicated to be between 0.5 and 5 μS/cm. For example, aconventional TDS meter indicates the total dissolved solids (TDS) of asolution, i.e. the concentration of dissolved solids in it. Sincedissolved ionized solids, such as salts and minerals, increase theconductivity of a solution, a TDS meter measures the conductivity of thesolution, estimates the total dissolved solids from that and displays itas ppm (parts per million). Tap water normally has between 220 and 350ppm measured with a conventional TDS meter.

The water purification apparatus 19 is arranged to provide purifiedwater having less than 10 ppm, such as less than 5 ppm or 0-2 ppmmeasured with a TDS meter, e.g. at 25° C. For example, the waterpurification apparatus 19 is arranged for providing purified waterhaving a conductivity of less than 0.5 μS/cm, such as less than 0.1μS/cm. Hence, the purified water has substantially no charge andsubstantially no conductivity. For example, the water purificationapparatus 19 is arranged for providing water with less conductivity thandistilled water.

The water purification apparatus 19 according to the embodiment of FIG.3 comprises a filter 25, a reverse osmosis device 26 and a deionizingfilter 27. The water purification apparatus 19 is connected to the waterinlet 18 for conducting water from a water supply network or similar tothe filter 25, which is illustrated by means of the arrow A in FIG. 3.The filter 25 is arranged for filtering off particulate solids. Forexample, the filter 25 is a sediment filter. For example, the filter 25is also arranged for removing chlorine and for softening the water. Thefilter 25 is, for example, arranged as a filter pack including aplurality of filters, such as one or more sediment filters, carbonfilters and softener filters. The water is then conducted to the reverseosmosis device 26, which is illustrated by means of the arrow B in FIG.3, for removing particles from the water and purifying the waterfurther. The water is then conducted to the deionizing filter 27, whichis illustrated by means of the arrow C in FIG. 3, for deionizing thewater. For example, the deionizing filter 27 is a double deionizingfilter. Then the purified water is conducted to the reservoir 20, whichis illustrated by means of arrow D in FIG. 3. Purified water can beconducted from the reservoir 20, which is illustrated by means of thearrow E, for washing the items 12 in the container 13 as describedabove.

With reference to FIG. 4 another embodiment of the water purificationapparatus 19 of the system 10 is illustrated. In the embodiment of FIG.4 the water purification apparatus 19 comprises a heater 28, the filter25, a carbon filter 29, a softener filter 30, the reverse osmosis device26, a first deionizing filter 27 and a second deionizing filter 31.

The heater 28 is arranged for heating the water from the water inlet 18.Hence, the heater 28 is arranged for heating the water beforepurification thereof. The heater 28 is, for example, arranged forheating the water to 2030° C. or 25° C. The heater 28 is, for example,an immersion heater, such as a Backer 3000W immersion heater. Forexample, the heater 28 is arranged between the water inlet 18 and thefilter 25.

In the embodiment of FIG. 4, the filter 25 is a sediment filter forfiltering off particles having a size of down to 5 microns. The carbonfilter 29 is arranged for filtering off particles and for removingchlorine if necessary. For example, the carbon filter 29 is a carbonfilter for filtering off particles of a size down to 10 microns. Thesoftener filter 30 is, for example, a phosphate filter, for removingchemical particles from the water, such as chlorine. Alternatively, thesoftener filter 30 is another carbon filter or a combinedcarbon/softener filter for softening the water.

The water purification apparatus 19 according to FIG. 4 also comprisesat least one booster pump 32, such as an Aquatec 8800, for pressurizingthe reverse osmosis device 26 to a working pressure of, for example, 689kPa (100 psi). For example, the booster pump 32 is arranged to provide asuitable working pressure of the reverse osmosis device 26.Alternatively, other types of pumps are used to provide suitable workingpressure for the reverse osmosis device 26.

The reverse osmosis device 26 is arranged between the softener filter 30and the first deionizing filter 27. The reverse osmosis device 26 isarranged for further removal of particles in the water. The reverseosmosis device 26 is, for example, arranged for removing bacteria,viruses and chemicals from the water. For example, the reverse osmosisdevice 26 is or includes an Axeon-HF4 Series Membrane Element, such as aHF4-4014 from Axeon Water Technologies. The size and number of reverseosmosis devices 26 and booster pumps 32 may vary depending on the amountof purified water to be produced. For example, the water purificationapparatus 19 according to one embodiment produces about 1.100 litres perday, i.e. 0.79 l/min. For example, the water purification apparatus 19is arranged for producing 0.2-5 l/min, 0.5-2 l/min or 0.5-1 l/min.

The first and second deionizing filters 27, 31 are arranged fordeionizing and further purifying the water. According to the embodimentof FIG. 4 the deionizing filters 27, 31 are arranged between the reverseosmosis device 26 and the reservoir 20 for purified water, wherein waterfrom the reverse osmosis device 26 is conducted to the deionizingfilters 27, 31. The first and second deionizing filters 27, 31 are, forexample, a double filter, such as US Water Aquapurion DI-BB220 Dual4.5″×20″ Filtration System. The deionizing filters 27, 31 are, forexample, arranged as interchangeable units. Alternatively, thedeionizing filters 27, 31 comprise a tank with a deionizing material,wherein the deionizing material is replaceable.

The reservoir 20 is connected to the deionizing filters 27, 32, forreceiving purified water therefrom. According to the illustratedembodiment a water purity meter 33, such as a TDS meter, is arranged forchecking the purity of the water. For example, the water purity meter 33is arranged between the deionizing filters 27, 32 and the reservoir 20for checking the purity of the water before conducting the purifiedwater to the reservoir 20. If the purified water contains contaminants,such as total dissolved solids, exceeding a predetermined threshold, itcan be an indication that the deionizing filters 27, 32 and/or any ofthe sediment filter 25, the carbon filter 29 and the softener filter 30,needs to be changed. For example, the TDS meter is a HM Digital DM-1Digital TDS Monitor. Alternatively, a conductivity meter is arrangedbetween the deionizing filters 27, 31 and the reservoir 20 for puritycontrol. The water is, for example, at a temperature of 25° C. duringthe measurement with the water purity meter 33.

The reservoir 20 is arranged for storing purified water. The reservoir20 is, for example, a pressure tank. For example, the reservoir 20 is apressure tank with a pressure of 34 to 48 kPa (5 to 7 psi) for obtaininga water pressure similar to that of the water supply network. Forexample, the reservoir 20 is arranged for providing a water pressuresimilar to the water pressure of the water entering the waterpurification apparatus 19. Alternatively, the reservoir 20 is anothertype of tank, such as an atmospheric tank. The reservoir 20 isdimensioned according to the application. For a system 10 in the form ofa household appliance serving a single family the reservoir 20 is, forexample, a 20-200 l tank. If the system 10 is for commercial use orserving a plurality of households the reservoir is, for example, a100-1000 l tank. For example, the reservoir 20 is a 10-1000 l tank, a20-500 l tank or a 50-100 l tank.

With reference to FIG. 5 the system 10 comprises a plurality of washingmachines 11 a-d, each having a container 13 for receiving items 12.According to FIG. 5 the system 10 comprises a single water purificationapparatus 19, wherein the water purification apparatus 19 providespurified water to all washing machines 11 a-d. In FIG. 5 the waterpurification apparatus 19 is connected to four washing machines 11 a-d.Hence, the water purification apparatus 19 is connected to one or morewashing machines 11, such as 1-10 washing machines 11. The waterpurification apparatus 19 is, for example, connected to one or moreconventional washing machines 11 a-d, wherein the system 10 comprisesthe one or more conventional washing machines 11 a-d. In the illustratedembodiment, the water purification apparatus 19 is connected to thewashing machines 11 a-d by means of the tubing 21 and the pumping device23 for conducting purified water to the washing machines 11 a-d. Thesystem 10 can be installed in present buildings as well as duringconstruction of new buildings.

With reference to FIG. 6 the system 10 comprises at least one washingmachine 11 and at least one dishwasher 24, wherein the waterpurification apparatus 19 is connected to the at least one washingmachine 11 and the at least one dishwasher 24 for providing purifiedwater thereto for washing of items. The washing machine 11 and thedishwasher 24 are, for example, household appliances for domestic use,wherein items, such as laundry and dishes, can be cleaned without use oftensides or detergents. In the embodiment of FIG. 6 the washing machine11 and the dishwasher 24 are connected to the reservoir 20 through thetubing 21, so that purified water from the water purification apparatus19 can be conducted to the washing machine 11 and the dishwasher 24. Itis understood that the system 10 can include a desired number of washingmachines 11 and/or dishwashers 24 and/or other household appliances forwashing items with water.

1. A system for washing items with water, comprising a water inlet and acontainer for receiving the items to be washed, wherein the systemcomprises a water purification apparatus for purifying water introducedthrough said water inlet to produce purified water, the waterpurification apparatus comprising at least one filter for filtering offparticulate solids, a reverse osmosis device, and at least onedeionizing filter, and, wherein the system further comprises a reservoirfor storing purified water produced by the water purification apparatus,said reservoir being connected to said water purification apparatus andsaid container, so that the items are washable inside the container withthe purified water.
 2. The system according to claim 1, wherein thewater inlet is arranged for connection to a municipal water supplynetwork.
 3. The system according to claim 1, comprising a pump forobtaining a working pressure of the reverse osmosis device and thedeionizing filter of 600-800 kPa.
 4. The system according to claim 1,wherein the reverse osmosis device is arranged between the filter andthe deionizing filter.
 5. The system according to claim 1, wherein thewater purification apparatus comprises, arranged in consecutive order, asediment filter, a carbon filter, a softener filter, the reverse osmosisdevice, a first deionizing filter and a second deionizing filter.
 6. Thesystem according to claim 1, comprising a heater arranged between thewater inlet and the filter for heating the water to 20-30° C. or 25° C.7. The system according to claim 1, wherein the water purificationapparatus is arranged for providing purified water with 0-2 ppm totaldissolved solids.
 8. The system according to claim 1, wherein the systemcomprises a washing machine for washing laundry, or a dishwasher.
 9. Amethod for washing items with water, comprising the steps of a)conducting water from a water supply to a water inlet of a system forwashing said items, b) conducting said water to a water purificationapparatus for purifying said water, c) filtering off particulate solidsfrom the water inside the water purification apparatus, d) purifying thewater by means of reverse osmosis inside the water purificationapparatus, e) filtering the water through at least one deionizing filterinside the water purification apparatus, f) conducting the purifiedwater to a reservoir for storing the purified water, g) conducting thepurified water from the reservoir to a container with the items to bewashed, and h) washing the items inside the container with the purifiedwater.
 10. The method according to claim 9, wherein in step a) the wateris conducted from a municipal water supply network to the water inlet.11. The method according to claim 9, wherein in step c) the water isconducted through a sediment filter, a carbon filter and a softenerfilter.
 12. The method according to claim 9, wherein the water, afterstep e), is purified to 0-2 ppm total dissolved solids.
 13. The methodaccording to claim 9, wherein the water, after step d), is conductedthrough a first deionizing filter and a second deionizing filter. 14.The method according to claim 9, wherein the items are washed withouttensides or detergents.